Lots of options given your timeframe. I would recommend taking the online AOPA mountain flying course regardless. AOPA and EAA have references for established courses. I am partial to a one-on-one course offered in Vail, Colorado. Very nice lady instructed me and took me around the Colorado Rockies including landings at the highest airport in North America (Leadville @ 9927 ft). The emphasis was on practical experience since my ground school was adequately covered with the AOPA course. The course can be tailored to your needs including time and terrain.